ELECTRIC LIGHTS. 17 



denser consists of three lenses, the front one being five 

 inches in diameter. This is shown in the cut (Fig. 8) 

 of the transverse section of it. The objective repre- 

 sented is also compound. This form of lantern is 

 made by Hawkridge at the Stevens Institute, Hobo- 

 ken, N. J., and called the' Experimenter's Lantern, be- 

 cause of its adaptability to many kinds of experimental 



Fig. 9. 



work, as well as to the exhibition of photographic trans- 

 parencies. 



Mr. L. J. Marcy, of Philadelphia, has, in an ingen- 

 ious manner, made a lantern jet which can be used 

 with alcohol, common gas, or hydrogen, to produce the 

 lime light. He calls it the triple jet. The engrav- 

 ing (Fig. 9) shows the lantern in section. Z being the 

 disc of lime, the gases ignited at w. This lantern is 

 compact, light, and has a very convenient arrangement 

 for holding slides, tanks, and so forth. 



